787 research outputs found
Effect of beating process to soda anthraquinone pulp of oil palm male flower spikes fibre
This study was carried out to investigate the effect of beating process to the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). OPMFS pulp was prepared according to chemical Soda-AQ pulping process. 60 gsm handsheet of oil palm male flower spikes paper were prepared from OPMFS pulp with four different beating times which are O revolution, 1000 revolutions, 2000 revolutions and 3000 revolutions. All physical and mechanical characteristics were investigated according to T APPi and MS ISO standards. The results show that overall physical and mechanical characteristics of POMPS paper were influenced and enhanced by beating process between O until 3000 revolutions. This research demonstrate some potential characteristics of palm oil male flower spikes (OPMFS) paper to be investigated as a newly explored non-wood based raw material for papermaking raw material for papermaking
Soda anthraquinone pulping of oil palm male flower spikes
This study was carried out to investigate the effect of beating process to the characteristics of pulp and paper produced from oil palm oil male flower spikes (OPMFS). OPMFS pulp was prepared according to chemical Soda-AQ pulping process. 60 gsm papersheet of oil palm male flower spiked were prepared from unbeaten and unbleached OPMFS Soda-AQ pulp. All optical, physical and mechanical characteristics were investigated according to TAPPI and MS ISO standards. OPMFS pulp recorded value of 6.42 s, 353 ml, 76.5 %, 36.7 % and 9.35 for drainage time, freeness, moisture content, screened yield percentage and Kappa number respectively..
The Effect of Block Ownership on Future Firm Value and Performance
This paper examines the performance of the investment decisions of block owners. The block ownership data is obtained from Dlugosz, Fahlenbrach, Gompers, and Metrick (2006). We find that firm valuation (measured by Tobin's Q), operating performance (measured by changes in return on assets) and stock performance (measured by excess buy and hold returns) are positively and significantly related to the previous years' level of block ownership both in terms of the size of the ownership and the number of blockholders. Our results are robust to endogeneity concerns. Regarding whether a specific blockholder is an “insider” or an “outsider” to the firm, we find that the ownership of “outside” blockholders is a key determinant in explaining future firm performance. Note though that this category makes up about two-thirds of the aggregate amount of blockholding in Dlugosz et al. (2006) database, and also includes all blockholders not classified in other categories. In general, we attribute the superior performance to the presence of more blockholders. We also find an inverse association between the volatility in blockownership and the ex-post firm performance measures
Injectable dual-gelling cell-laden composite hydrogels for bone tissue engineering
The present work investigated the osteogenic potential of injectable, dual thermally and chemically gelable composite hydrogels for mesenchymal stem cell (MSC) delivery in vitro and in vivo. Composite hydrogels comprising copolymer macromers of N-isopropylacrylamide were fabricated through the incorporation of gelatin microparticles (GMPs) as enzymatically digestible porogens and sites for cellular attachment. High and low polymer content hydrogels with and without GMP loading were shown to successfully encapsulate viable MSCs and maintain their survival over 28 days in vitro. GMP incorporation was also shown to modulate alkaline phosphatase production, but enhanced hydrogel mineralization along with higher polymer content even in the absence of cells. Moreover, the regenerative capacity of 2 mm thick hydrogels with GMPs only, MSCs only, or GMPs and MSCs was evaluated in vivo in an 8 mm rat critical size cranial defect for 4 and 12 weeks. GMP incorporation led to enhanced bony bridging and mineralization within the defect at each timepoint, and direct bone-implant contact as determined by microcomputed tomography and histological scoring, respectively. Encapsulation of both GMPs and MSCs enabled hydrogel degradation leading to significant tissue infiltration and osteoid formation. The results suggest that these injectable, dual-gelling cell-laden composite hydrogels can facilitate bone ingrowth and integration, warranting further investigation for bone tissue engineering
Simultaneous Quantitative Analysis of Olmesartan Medoxomil and Amlodipine Besylate in Plasma by High-performance Liquid Chromatography Technique
A rapid, simple and sensitive high-performance liquid chromatography (HPLC) method has been developed for quantification of olmesartan medoxomil (OLM) and amlodipine besylate (AM) in plasma. The assay enables the measurement of OLM and AM for therapeutic drug monitoring with a minimum detectable limit of 2 ng mL. The method involves a simple, one-step extraction procedure and analytical recovery was above 50%. The separation was performed on an analytical 250 × 4.6 mm Eurospher 100-5 C18 column. The wavelength was set at 239 nm. The mobile phase was a mixture of acetonitrile:0.05 M ammonium acetate buffer: 0.1 mL triethylamine at pH 6.8 was selected at a flow rate of 1.0 mL min. The calibration curve for the determination of OLM and AM in plasma was linear over the range 2–2500 and 8–10,000 ng mL AM and OLM. The coefficients of variation for interday and intraday assay were found to be <15%. The method can be applied to a pharmacokinetic and pharmacodynamic study of OLM and AM in a combined dosage form
Microscopic theory of vertical-transport phenomena in semiconductor heterostructures: Interplay between two- and three-dimensional hot-carrier relaxation
A theoretical analysis of vertical-transport phenomena in semiconductor heterostructures is presented. In particular, the scattering coupling between two- and three-dimensional states in multiple quantum wells is investigated. To this purpose, a fully three-dimensional approach for the description of both localized and extended states in the heterostructure is proposed. Starting from such three-dimensional states, obtained from a self-consistent Schrödinger-Poisson calculation, a Monte Carlo solution of the corresponding Boltzmann transport equation is performed. In contrast to various phenomenological transport models, the present simulation scheme allows a kinetic description, i.e., based on microscopic scattering rates, of vertical transport across a generic heterostructure. Our results provide a rigorous description of hot-carrier relaxation between extended and localized states. This simulation scheme has been applied to finite multiple quantum wells with different geometries and doping profiles. A detailed analysis of the electron current as a function of temperature in quasiequilibrium conditions shows good agreement with experimental results. Moreover, in non-equilibrium conditions (i.e., hot-carrier regime) the scattering coupling between three- and two-dimensional states is found to play a significant role in modifying the carrier mobility as well as the fraction of conducting electrons
Discovery of Human Signaling Systems: Pairing Peptides to G Protein-Coupled Receptors
The peptidergic system is the most abundant network of ligand-receptor-mediated signaling in humans. However, the physiological roles remain elusive for numerous peptides and more than 100 G protein-coupled receptors (GPCRs). Here we report the pairing of cognate peptides and receptors. Integrating comparative genomics across 313 species and bioinformatics on all protein sequences and structures of human class A GPCRs, we identify universal characteristics that uncover additional potential peptidergic signaling systems. Using three orthogonal biochemical assays, we pair 17 proposed endogenous ligands with five orphan GPCRs that are associated with diseases, including genetic, neoplastic, nervous and reproductive system disorders. We also identify additional peptides for nine receptors with recognized ligands and pathophysiological roles. This integrated computational and multifaceted experimental approach expands the peptide-GPCR network and opens the way for studies to elucidate the roles of these signaling systems in human physiology and disease. Video Abstract: Features learned from comparative sequence and structural analyses enabled prediction of peptide ligands for orphan GPCRs that, when coupled with functional validation, expose physiologically relevant signaling systems. © 2019 The Author(s
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